Thirteen investigators are requesting funds for an ion trap mass spectrometer (MS) equipped with electro spray, nanoelectrospray, and APCI (atmospheric pressure chemical ionization) ion sources. The ion trap MS, which is not available in the Albany research community, will be used for high sensitivity LC-MS/MS, peptide sequence, proteomics and multiple stage collision induced dissociation [MS(n)] analysis. These investigators are funded by 10 NIH and 3 NSF grants that will benefit directly from use of an ion trap MS. Seven of the investigators will use high sensitivity MS/MS interfaced to automated database searches for rapid identification of peptide/protein sequence, i.e. proteomics. Specific research areas include: metal-induced immunopathology, M. tuberculosis interaction with macrophages, the role of mitochondria in apoptosis, protein translocation across membranes, vascular biology, stress gene regulation in archea, mitosis associated proteins, and PCB estrogenic effects in human breast cells. Six of the investigators will use MS (N) analysis for molecular structure elucidation, specifically; unusual oligosaccharides, peptide disulfide bridge assignment, extensively cross- linked peptides/proteins from a marine organism adhesive, metabolite analysis, complex organic ground water pollutants, and radiation-induced DNA modifications. All co-investigators collaborate currently with the Biological Mass Spectrometry Core at the Wadsworth Center. The Principal Investigator (Director of the Core) has extensive experience in biological mass spectrometry and the management of a multi-instrument, multi-user facility. The ion trap MS will be integrated into this core. The Wadsworth Center houses the only biological MS core facility in the greater Albany area, and it has an established record of both routine analysis and research collaboration with investigators at Albany Medical College, SUNY Albany, and Rensselaer Polytechnic Institute. Award of this instrument will afford the only local access of automated MS/MS proteomic data base searching and MS(n) analysis for the investigators. At this time we request a Finnigan LCQ Deca, with the Seaquest database search program, and equipped with a Protana nanoelectrospray ion source, as the instrument best suited to these diverse applications.